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This peanut butter mug cake recipe is moist, fluffy, and full of rich peanut butter flavor. Made with just three ingredients, it takes less than a minute to bake.
Love mug cake recipes? Try my almond flour mug cake, protein mug cake, or chocolate chip mug cake next.
Everyone needs a go-to dessert that can be made with minimal effort when the cravings strike. My foolproof peanut butter mug cake recipe ticks those very boxes, and it’s become an almost nightly tradition!
Table of Contents
Why I love this recipe
- It’s so darn easy. Just mix up your batter, pour it into your mug, and pop it in the microwave. It doesn’t get easier than this.
- Easy to customize. There’s plenty of room to customize this recipe so you can make it different every time.
- Microwave and oven options. I prefer the microwave because it’s quick, but if I’m making mug cakes for the whole family, I always use the oven.
- Secretly healthy. Like my cinnamon roll in a mug, this mug cake has a decent amount of protein and minimal sugar, though you’d never guess by how tasty it is.
★★★★★ REVIEW
“Love this cake! It’s easy, it’s delicious, and the texture is good too. I do use a brown sweetener in it and sometimes add a little cinnamon to it. But even without the cinnamon, it’s great!” – Kristy
Ingredients needed
- Peanut butter. Make sure the peanut butter you use has a smooth and drippy texture. I like to use all-natural smooth by Skippy’s or Trader Joe’s. Peanut butter can be swapped for any type of nut or seed butter, like sunflower seed butter, almond butter, or cashew butter.
- Sugar. I used granulated white sugar, but if you’d prefer a more molasses flavor, use light brown sugar. Sugar substitutes will also work.
- Egg. For moisture and to bind the dry ingredients.
- Baking powder. It’s optional, but it gives the mug cake that extra fluffiness.
- Mix-ins. I’ve included a ton of suggestions in the variations section.
How to make a peanut butter mug cake
I’ve included step-by-step photos below to make this recipe easy to follow at home. For the full printable recipe instructions and ingredient quantities, scroll to the recipe card at the bottom of this post.
Step 1- Make the batter. In a small mixing bowl, add all your ingredients and stir to combine. Transfer the batter to a greased large mug, ramekin, or shallow bowl.
Step 2- Microwave. Microwave the mug cake for 45 seconds- 1 minute, or until a toothpick inserted comes out clean. Remove the cake from the microwave and let it sit for one minute before serving.
How to make this in the oven
If you’d rather make the mug cake in the oven, it’s easy. Just preheat the oven to 350F/180C and grease a 6 or 8-inch ramekin with cooking spray. Make the batter, pour it into the ramekin, and bake for 8-10 minutes or until a toothpick comes out clean.
Arman’s recipe tips
- Avoid overcooking. Everyone’s microwave is different, so the cooking time may vary. I recommend checking the cake every 30 seconds, and if it’s not cooked after 1 minute, microwave it in 20-second bursts until it’s fully cooked.
- If you have a microwave safe cereal bowl, you can use that instead of a ramekin. This is a better option if you are worried that there may be overflow.
- If the batter looks too thick, I like to add 1-2 tablespoons of almond milk.
Flavor variations
- Peanut butter chocolate chip. Add 1-2 tablespoons of dark chocolate chips to the batter and on top of the mug cake.
- Chocolate peanut butter. Add 1-2 tablespoons of cocoa powder to the batter.
- Peanut butter and jelly. Swirl 1-2 teaspoons of jelly into the batter.
- Cut the carbs. For a low-carb version, swap out the sugar for allulose.
- Add toppings. Top the fresh mug cake with whipped cream, vanilla ice cream, or caramel sauce.
- Enhance the flavor. Add a sprinkle of sea salt or ¼ teaspoon of vanilla extract.
More delicious mug cakes to try
Peanut Butter Mug Cake
Ingredients
- 3 tablespoons peanut butter
- 1-2 tablespoons sugar
- 1 large egg
- 1/2 teaspoon baking powder optional
Instructions
- In a small mixing bowl, add all your ingredients and whisk together, until combined.
- Transfer your mug cake batter into a greased microwave-safe ramekin or cereal bowl. Microwave for 45 seconds-1 minute. Remove from the microwave and let sit for a minute, before eating.
Oven Instructions
- Preheat the oven to 180C/350F. Grease an oven-safe ramekin (6-8 inches) with oil. Make the batter before transferring to the ramekin. Bake for 8-10 minutes.
Nutrition
Originally published October 2020, updated and republished April 2024
Delicious! I rehydrated PBFit organic low calorie powdered PB and used some organic chocolate chips sweetened with stevia and allulose sweetener. It was a wonderful low calorie snack that satisfied my cravings. I’m loving all these mug recipes! Thanks!
I dont know what I like more-mug cake or peanut butter. Definitely need to try!
Fabulous made with Swerve (2 Tbsp) and natural peanut butter. Definitely add the chocolate chips!
What about powdered peanut butter such as PB2? How could that work?
You could try!
Hi Arman,
Many of your recipes have become staples in my home, especially the keto’s. It’s hard to find keto recipes that work, with so few ingredients. The mug cakes not only taste great, but are filled with healthy nutrients as fiber and protein. I’ve been known to tweak a bit by adding nuts to some. These are all keepers to be download to my digital app: “My Recipe Box”, so they’re forever handy.
With much gratitude, Jeannie
Thanks so much, Jeannie!
Love this cake! It’s easy, it’s delicious, and the texture is good too. I do use a brown sweetener in it, and sometimes add a little cinnamon to it. But even without the cinnamon, it’s great!
It’s good! Make it!
can’t wait to try these. Not only do they look delicious, but the ingredients are also inexpensive and fast to prepare and cook.
This way I’m saving money and these days every little bit counts.
Thank you so much
Great Grandma on Social Security